1. Field of the Invention
The present invention relates to a cooling apparatus for an auxiliary fuel tank in an outboard motor. More specifically, the invention is directed to an improvement in an apparatus in which an auxiliary fuel tank capable of storing extra fuel returning from a fuel injection valve side of an engine, and a high-pressure fuel pump for pumping fuel stored in the auxiliary fuel tank to the fuel injection valves of the engine, are housed in an engine cover. The engine cover is configured to cover the engine, a water jacket which cools the stored fuel is formed on the auxiliary fuel tank, a water pump which is driven by the engine to supply external water is connected to the inlet of the water jacket, and a discharge passage which is connected to the outlet of the water jacket.
2. Description of the Prior Art
A cooling apparatus for an auxiliary fuel tank in an outboard motor is already known as disclosed in, for example, Japanese Patent Laid-Open No. 9-144617.
In a cooling apparatus for an auxiliary fuel tank in an outboard motor, to maintain the durability of a water jacket, it is necessary that no cooling water remain in the water jacket when the engine is stopped. However, no consideration has been given to such a problem of conventional types of cooling apparatus. In the cooling apparatus disclosed in the prior art, since the inlet and the outlet of the water jacket are provided in the rear wall thereof, if the outboard motor is tilted up, the inlet and the outlet are disposed at an upper portion of the water jacket. Therefore cooling water remains in the water jacket, decreasing the durability thereof.
The present invention has been developed in view of the above-described problem; an object of the present invention is to provide a cooling apparatus for an auxiliary fuel tank in an outboard motor, which is capable of reliably discharging cooling water from the water jacket of the auxiliary fuel tank when an engine is stopped, and even when the outboard motor is tilted up.